Non-symmetric rotating triangulation issue (quadratic elts>5.10.1)
requested to merge eg/vtk:non_symmetric_rotating_triangulation_issue_with_quadratic_elements into master
the above patch first suggested by John Platt 2 years ago on the mailing list restore the <5.10.1 behavior regarding the proper display of boundaries between quadratic elements.
the current implementation will fail to properly render quadratic elements with a rotated normal.